“Last quarter, each of Apple’s (AAPL) iTunes accounts spent an average of $3.29, down 24% year over year,” Philip Elmer-DeWitt reports for Fortune.

“At a high level,” Morgan Stanley’s Katy Huberty writes in a note to clients Wednesday, “this raises concerns about Apple’s ability to monetize the new base of emerging market customers.”

“But by the end of the year, App Store sales will have more than taken up the slack, Huberty predicts,” P.E.D. reports. “And she sees several ways Apple could tap into one of the company’s great unheralded resources: 800 million iTunes accounts, most of them attached to credit cards.”

She ticks off three new opportunities:
• Streaming music
• Mobile payments
• iWatch

P.E.D. reports, “To these three new revenue sources, Asymco‘s Horace Dediu adds a fourth… ‘Why not bring iTunes to Android?'”

Read more in the full article here.

MacDailyNews Take: Well, Apple already makes iTunes for the world’s preeminent Mac knockoff, so why not for the iPhone/iPad knockoff, too?

[Thanks to MacDailyNews Readers “Sarah” and “Dan K.” for the heads up.]